JPH0227509A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To improve the reliability of an action by constituting a 1st leader line structure of a magnetic substance and eliminating magnetic noises which work to a magnetic yoke from the outside through the leader line structure. CONSTITUTION:The title head is constituted of a one-layer or multilayer spiral coil 5, the magnetic yoke 2 interlinking said coil and having a magnetic gap G on its part, the 1st leader line structure 3 and a 2nd leader line structure 6 connected to the outside edge part 5b on the outside of said coil 5. The 1st leader liner structure 3 which approaches the magnetic yoke 2 in the center part of said coil 5 is constituted of a nonmagnetic substance. Therefore, the magnetic noises of the outside, etc., can be prevented from being transmitted to the magnetic yoke 2 through the 1st leader line structure 3 and the unstable fluctuation of faint magnetic flux which is transferred between a storing medium and the title head through the magnetic gap G of the magnetic yoke 2 can be surely prevented. Thus, the reliability of the action can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thin film magnetic head, and particularly to a thin film magnetic head that is less susceptible to external magnetic noise.

[Conventional technology]

For example, in response to the increase in the recording density of information on magnetic surface recording media such as magnetic tapes and magnetic disks, miniaturization of magnetic heads that record and reproduce information using magnetic flux as a medium for these storage media is easy. Thin film magnetic heads have come into use.

Conventionally, such thin film magnetic heads include, for example,
A structure disclosed in Japanese Unexamined Patent Publication No. 55-84019 is known.

In other words, a spiral coil is formed by applying photolithography to a conductive thin film, and a part of this spiral coil is sandwiched through an insulating film and connected at the center so that the spiral coil is linked to the outside. a yoke structure consisting of an upper magnetic thin film and a lower magnetic film forming a magnetic gap; A thin film magnetic head is constituted by one lead wire and a second lead wire formed at the outer end of the spiral coil at the same time as the spiral coil.

[Problem to be solved by the invention]

However, in the conventional thin film magnetic head having the above structure, there is a yoke structure consisting of magnetic thin films connected to each other within the center of the spiral coil, and a magnetic thin film connected to the inner end of the spiral coil. Because the magnetic noise introduced from the outside through the first lead wire made of a magnetic material is in close proximity to the first lead wire formed by This inevitably affects the weak magnetic flux exchanged between the thin-film magnetic heads, and this weak magnetic flux causes unstable fluctuations, so-called wiggles, which reduce the reliability of the thin-film magnetic head's operation. There's a problem.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a thin-film magnetic head that improves operational reliability by eliminating magnetic noise that acts on the magnetic yoke from the outside through a leader line structure.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means to solve the problem]

A brief overview of typical inventions disclosed in this application is as follows.

That is, the thin film magnetic head of the present invention includes a spiral coil having one layer or multiple layers, a magnetic yoke that interlinks with the spiral coil and has a magnetic gap in a part, and an inner end on the center side of the spiral coil. A thin film magnetic head comprising a first leader wire structure connected to a spiral coil, and a second leader wire structure connected to an outer end of a spiral coil, the first leader wire structure being a non-magnetic wire. It is made up of the body.

Further, the thin film magnetic head of the present invention includes a spiral coil having one layer or multiple layers, a magnetic yoke interlinked with the spiral coil and having a magnetic gap in a part, and an inner end on the center side of the spiral coil. a first leader line structure connected to the section;
A thin film magnetic head comprising a second leader wire structure connected to the outer end of the spiral coil, the first leader wire structure being made of a magnetic material, and the first leader wire structure The connection end to the inner end of the spiral coil forms a branch part surrounding the magnetic yoke.

[Effect]

According to the former thin-film magnetic head described above, the first lead wire structure near the magnetic yoke in the center of the spiral coil is made of a non-magnetic material, so external magnetic noise etc. The magnetic flux is prevented from being transmitted to the magnetic yoke through the lead wire structure, and unstable fluctuations in the weak magnetic flux exchanged with the storage medium through the magnetic gap of the magnetic yoke are reliably prevented, increasing the reliability of the operation of the thin-film magnetic head. can improve sex.

Further, according to the latter thin film magnetic head described above, the first lead wire structure close to the magnetic yoke in the center of the spiral coil is made of a magnetic material, and the connection end to the spiral coil is connected to the magnetic yoke. For example, by making the magnetic resistance at the branch part of the first leader line structure smaller than that of the magnetic yoke, it is possible to branch out magnetic noise that comes from outside through the first leader line structure. The magnetic yoke can be guided around the magnetic yoke by the section.

This prevents the weak magnetic flux exchanged with the storage medium through the magnetic gap of the magnetic yoke from fluctuating unstablely due to external magnetic noise, improving the reliability of the operation of the thin-film magnetic head. can.

[Embodiment 1] FIG. 1 is a plan view showing the main parts of a thin film magnetic head which is an embodiment of the present invention.

For example, on a non-magnetic substrate 1 made of alumina or the like, a lower magnetic film 2a constituting a magnetic yoke 2 and a first leader line structure 3 are formed in a predetermined shape.

In this case, the first leader line structure 3 is made of, for example, a non-magnetic conductor different from the lower magnetic film 2a.

The lower magnetic film 2a and the first leader wire structure 3 are hidden by an insulating film 4 deposited in a predetermined shape, and a spiral coil 5 made of a conductor is formed on the insulating film 4. has been done.

The inner end 15a of the spiral coil 5 on the central side is electrically connected to the end of the lower first leader wire structure 3 through the through hole 4a formed in the insulating film 4 located below. There is.

Further, the outer end 15b of the spiral coil 5 is integrally connected to the east 2 leader wire structure 6, which is formed of the same conductor as the spiral coil 5.

Further, an upper magnetic film (not shown) that pairs with the lower magnetic film 2a is deposited on the spiral coil 5 via an insulating film (not shown), and the upper magnetic film and the lower magnetic film 2a are bonded together. are connected to each other at the center of the spiral coil 5 through a through hole 7a (not shown) formed in the insulating film, and are connected to the outside of the spiral coil 5 at the outer edge of the substrate 1. By forming a magnetic gap G at the facing position, a magnetic yoke 2 interlinked with the spiral coil 5 is constructed.

Then, the magnetic gap G of the magnetic yoke 2 is brought close to the magnetic surface of the storage medium (not shown), and in this state, the spiral coil 5 is connected to the second leader wire structure 6 and the first leader wire structure 3.
When an electrical signal modulated into a waveform corresponding to predetermined information is transmitted from an external control device (not shown) through the magnetic gap G, leakage magnetic flux is formed in the magnetic gap G, which magnetizes the magnetic surface of the storage medium. At the same time as the recording operation is performed, the information reproduction operation is performed by detecting the current induced in the spiral coil 5 by the magnetic flux acting on the magnetic yoke 2 from the storage medium side that has been magnetized in a predetermined state. .

Here, since the magnetic flux exchanged between the magnetic yoke 2 and the storage medium via the magnetic gap G is generally very weak, for example, as in the conventional case, the magnetic yoke 2 When the first leader wire structure 3 connected to the inner end 5a of the spiral coil 5 in a state close to the spiral coil 5 is made of a magnetic material, external magnetic noise etc. may damage the first leader wire structure. 3, it is unavoidable that the magnetic yoke 2 is adversely affected by the magnetic force, and there is a problem in that a harmful phenomenon such as the above-mentioned wiggle that destabilizes the operation of the thin film magnetic head occurs.

However, in the case of this embodiment, since the first leader line structure 3 is made of a non-magnetic material, external magnetic noise is transmitted through the first leader line structure 3 and acts on the magnetic yoke 2. can be prevented.

This prevents harmful phenomena such as wiggle from occurring and improves the reliability of the operation of the thin film magnetic head.

[Embodiment 2] FIG. 2 is a plan view showing the main parts of a thin film magnetic head according to another embodiment of the present invention.

In the case of the second embodiment, the first leader line structure 8 formed on the substrate 1 is simultaneously formed of the same magnetic material as the lower magnetic film 2a, and the inner end 15a of the spiral coil 5 is The connection end 8a to the magnetic yoke 2a forms a branch 8b that surrounds the magnetic yoke 2 composed of a lower magnetic film 2a and an upper magnetic film (not shown), and the branch is formed so that the magnetic resistance is sufficiently smaller than that of the magnetic yoke 2. Embodiment 1 shows that the cross-sectional area of the portion 8b is set sufficiently large.
This is different from the case of .

As a result, harmful magnetic flux due to magnetic noise that comes from the outside to the magnetic yoke 2 side via the first leader wire structure 8 made of magnetic material is guided to bypass the magnetic yoke 2. Harmful magnetic flux can be prevented from passing through the magnetic yoke 2.

As a result, the adverse effects of external magnetic noise on the weak magnetic flux formed in the magnetic gap G of the magnetic yoke 2 when transmitting and receiving target information to and from a storage medium (not shown) are alleviated, and the reliability of the operation of the thin-film magnetic head is improved. can be improved.

In addition, in the case of the second embodiment, the first leader line structure 8 is
By forming the lower magnetic film 2a constituting the magnetic yoke 2 using the same magnetic material, it can be manufactured using the same number of steps as the conventional method, and there is no disadvantage of an increase in the number of steps.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the Examples and can be modified in various ways without departing from the gist thereof. Nor.

〔Effect of the invention〕

A brief overview of typical inventions disclosed in this application is as follows.

The thin film magnetic head of the present invention includes a spiral coil having a single layer or multiple layers, a magnetic yoke interlinked with the spiral coil and having a magnetic gap in a part, and an inner end on the center side of the spiral coil. A thin film magnetic head comprising a first lead wire structure connected to the coil, and a second lead wire structure connected to an outer end of the spiral coil, the thin film magnetic head comprising: a first lead wire structure connected to the spiral coil;
Since the lead wire structure is made of non-magnetic material, the first wire near the magnetic yoke in the center of the spiral coil
Since the leader wire structure is made of a non-magnetic material, it is possible to prevent external magnetic noise from being transmitted to the magnetic yoke through the first leader wire structure, and it is possible to prevent external magnetic noise from being transmitted to the magnetic yoke through the magnetic gap between the magnetic yoke and the storage medium. Unstable fluctuations in the weak magnetic flux sent and received are reliably prevented, and the reliability of the operation of the thin-film magnetic head can be improved.

Further, the thin film magnetic head of the present invention includes a one-layer or multi-layered spiral coil, a magnetic yoke interlinked with the spiral coil and having a magnetic gap in a part, and an inner inner part of the central side of the spiral coil. A thin film magnetic head comprising a first leader wire structure connected to an end portion and a second leader wire structure connected to an outer end portion outside the spiral coil, the first leader wire structure being connected to an outer end portion of the spiral coil. The structure is made of a magnetic material, and the connection end of the first leader wire structure to the inner end of the spiral coil forms a branch part surrounding the magnetic yoke, so that, for example, the first leader wire By making the magnetic resistance at the branch part of the structure smaller than that of the magnetic yoke, magnetic noise introduced from the outside through the first leader line structure can be guided by the branch part to bypass the magnetic yoke, and the magnetic yoke The weak magnetic flux exchanged with the storage medium through the magnetic gap is prevented from fluctuating unstably due to external magnetic noise, and the reliability of the operation of the thin-film magnetic head can be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the main parts of a thin film magnetic head according to an embodiment of the present invention, and FIG. 2 is a plan view showing the main parts of a thin film magnetic head according to another embodiment of the invention. DESCRIPTION OF SYMBOLS 1... Substrate, 2... Magnetic yoke, 2a... Lower magnetic film, 3... First leader line structure, 4... Insulating film, 4
a... Through hole, 5... Spiral coil, 5a... Inner end, 5b... Outer end, 6... Second leader wire structure,
7a... Through hole, 8... First leader line structure, 8a...
・Connection end, 8b...branch part, G...magnetic gap.

Claims (1)

[Claims] 1. A spiral coil having a single layer or multiple layers, a magnetic yoke interlinked with the spiral coil and having a magnetic gap in part, and an inner end on the center side of the spiral coil. A thin film magnetic head comprising a first leader wire structure connected to the spiral coil and a second leader wire structure connected to an outer end portion of the spiral coil, the first leader wire structure being non-conductive. A thin film magnetic head characterized by being made of a magnetic material. 2. A spiral coil having one layer or multiple layers, a magnetic yoke interlinked with the spiral coil and having a magnetic gap in a part, and a first magnetic yoke connected to the inner end on the center side of the spiral coil. A thin film magnetic head comprising a leader wire structure and a second leader wire structure connected to an outer end of the spiral coil, wherein the first leader wire structure is made of a magnetic material, and the first leader wire structure is made of a magnetic material; A thin film magnetic head characterized in that a connecting end of the first lead wire structure to the inner end of the spiral coil forms a branch portion surrounding the magnetic yoke.